Proper antituberculosis chemotherapy may not prevent occurrence or progression of endobronchial involvement in patients with pulmonary tuberculosis. We previously reported a higher incidence of endobronchial involvement in adults with lower lung field tuberculosis (LLFTB). We evaluated the value of roentgenographic and fiberbronchoscopic findings in predicting the outcome of adults with LLFTB after 9 months of antituberculosis chemotherapy. The most common change on chest roentgenograms among 101 patients with LLFTB was consolidation, followed by cavitary lesion, lung collapse, and solitary mass. Intrathoracic lymphadenopathy (hilar and/or mediastinal lymphadenopathy) was found in 12 cases. Sputum smear for acid-fast bacilli was positive in 64 patients, and sputum culture for tuberculous bacilli was positive in 37 of 50 patients. Endobronchial involvement was found in 45 of 63 patients who underwent fiberbronchoscopic examination. Of these 45, 18 had ulcerative granuloma, 12 had fibrostenosis, eight had submucosal infiltration, and seven had mucosal redness and swelling. A higher incidence of endobronchial involvement was found in the patients with LLFTB when they presented with roentgenographic findings of pulmonary consolidation, lung collapse, or associated intrathoracic lymphadenopathy. The outcome seemed unfavorable in the patients with LLFTB who presented with roentgenographic findings of lung collapse or pulmonary consolidation, or in those who presented with fiberbronchoscopic findings of fibrostenosis or ulcerative granuloma. Our results show that roentgenographic and fiberbronchoscopic findings are of value in predicting outcome of patients with LLFTB. With proper antituberculosis chemotherapy and close follow-up, fiberbronchoscopy may be clinically indicated in patients with LLFTB to assess the presence and severity of endobronchial involvement. Early surgical intervention can be considered in those with severe endobronchial involvement before serious sequelae occur.